Correcting errors that occur during the processing of electromagnetic waves and signals (hereinafter “waves”) is sometimes difficult. These waves may be used for many different purposes. For example, they may be processed in order to convey intelligence, such as by attenuating and/or amplifying electromagnetic wave characteristics, for instance, as is seen when modulating amplitude, frequency or phase of an electrical current or radio frequency (RF) wave to transmit data. As another example, power may be conveyed along a wave in a controlled fashion by attenuating and/or amplifying electromagnetic wave characteristics, such as is seen when modulating voltage or current in a circuit. Moreover, the uses may be combined, such as when intelligence may be conveyed through a wave by processing power characteristics.
Because low frequency waves, such as 60 Hz power waves, may need different processing techniques than high frequency waves such as 24 GHz radar waves, it is common practice to use different components, with different characteristics, for different waves. For example, a switching semiconductor used within a computer for 60 Hz power waves has different power handling characteristics from a power semiconductor used in a 24 GHz radar system. Each of these systems may produce errors in the processed signal, however, due to errors that may be introduced into some of the characteristics of the electromagnetic wave during signal processing.
For example, in phase modulation systems, errors may occur in the phase of the output signal from errors introduced during the modulation process. In these wave processing systems and others, the processing system must oftentimes be calibrated during manufacturing and/or at periodic intervals during use to reduce the errors introduced into the signal during processing. Calibrating the processing system in this way requires that a system be taken out of service or causes delay and expense in manufacturing the system.
Thus, it would be beneficial to calibrate the system by adaptively processing in an ongoing basis during operation, to closely re-produce the desired characteristics of the electromagnetic input wave with predetermined (e.g., idealized) wave characteristics during wave processing. Accordingly, it would be helpful to the art of electromagnetic processing to provide efficient, and at the same time, accurate techniques for correcting electromagnetic waves during signal processing.